Boat hull design



Feb. 2, 1965 T. L. FAUL ETAL 3,157,792

BOAT HULL DESIGN Filed May 16, 1963 3 Sheets-Sheet 1 Thomas L. F au/ Char/es W. W/H/w/z ATTORNEY Feb. 2, 1965 T. 1.. FAUL ETAL 3,

BOAT HULL DESIGN Filed May 16, 1963 3 Sheets-Sheet 2 I l0 7 o 3 m 0- l olzr 5 0 JZZI Thomas L F IONIXENTORS Char/e5 W W/f/ha/Z Feb. 2, 1965 T. FAUL ETAL BOAT HULL DESIGN 3 Sheets-Sheet 5 Filed May 16, 1965 MK 3 m M v WWW W 5 mm BY M g ATTORNEY 3,167,792 BOAT HULL DEIGN Thomas L. Fanl, Shaneateies, N.Y., and Charles W. Wittholz, Silver Spring, Md assignors to Lone Star Boat Company, Plano, Tern, a corporation of Texas Filed May 16, 1963, Ser. No. 280,796 1 Claim. (Cl. 9-6) This invention has to do with boats and is particularly concerned with a novel boat hull form and configuration.

The hull design which is the subject matter of this application is primarily applicable to relatively small boats, such as pleasure boats.

In relatively light pleasure boats which are intended to run at high speeds, it is desirable to have a hull with nonpounding characteristics, in order to reduce to a minimum the shock impact against waves or swells in order to make the boat more comfortable to the occupants at both low and high speeds.

In order to secure this non-pounding characteristic, it is necessary to have a high dead rise angle at the bow to split the waves without shock, and to have agenerous but more gradual dead rise on the running bottom of the hull at higher speeds. Preferably at high speeds the width of the running bottom should be considerably less than the desirable beam or width for required passenger accommodation.

' However, a hull of such general design has low stability on high speed turns, causing a diving action at the bow, as well as creating a possibility of the boat turning over if a turn is taken too fast.

The present invention is intended to provide the desirable features mentioned above, and at the same time provide such a hull which does not have the undesirable features of low stability, tendency to dive at the bow, and the possibility of turning over in a turn taken at high speed.

This object is accomplished by providing corresponding auxiliary planing surfaces beginning at the bow on each side of the hull, and running longitudinally toward the stern of the boat.

Such auxiliary planing surfaces act as planing areas during turns at high speed, stabilize the hull, minimize the lean of the hull into the turn to an acceptable and safe angle, and prevent increase in trim angle during a high speed turn.

By employing such auxiliary planing surfaces, the boat goes through a turn much in the same attitude that it goes on a straight course but without losing speed, without raising or lowering the bow, and with a moderate lean into the turn.

When the hull runs on a straight course at a moderately high speed, the auxiliary planing surfaces are free of the water and ride above the water level. 7

Longitudinal channels are formed along the bottom of the boat on each side of the keel which are rather deep at the how but become shallower as they continue along the bottom of the boat. These channels contain all spray and convert it into diverging masses of water split by the bow and keel, adding dynamic lift to the boat, as will be hereinafter explained.

Spray to each side of the boat is virtually eliminated.

Other and further objects of the invention will become apparent upon reading the detailed specification hereinafter following, and by referring to the drawings annexed hereto.

Suitable embodiments of the invention are shown in the attached drawings, wherein:

FIGURE 1 is a side elevational view of a boat having a hull incorporating the novel design;

FIGURE 11 is a bottom plan view of the boat shown in FIGURE I;

United States Patent 3,1h7fl92 Patented Feb. 2, 1965 FIGURE III is a transverse cross-sectional view taken along the line III-III of FIGURE I;

FIGURE IV is a transverse cross-sectional view taken along the line IVIV of FIGURE 1;

FIGURE V is a transverse, cross-sectional view taken along the line V-V of FIGURE I;

FIGURE VI is a bottom plan view of the boat employing the novel design, illustrating by cross lines the wetted area of the bottom of the .boat running on a straight course at relatively low speed;

FIGURE VII is a bottom plan view of the boat illustrating the wetted area of the bottom of the boat running on a straight course at a medium speed;

FIGURE VIII is a bottom plan view of theboat showing the wetted area of the bottom of the boat while turn ing at a relatively high speed;

FIGURE IX is a side elevational view of a modified form of the novel hull design;

FIGURE X is a bottom plan view of such modified form; and

FIGURE XI is a transverse, cross-sectional view taken along the line XI-XI of FIGURE IX.

Numerical references are employed to designate the various parts shown in the drawings, and like numerals indicate the like parts through the various figures of the drawings. 7 i

The numeral 1 indicates the general hull of the boat which may be made of fiberglass impregnated plastic, wood, aluminum or any other suitable material.

The hull includes a relatively sharp keel 2 at the bow which is bordered on each side by relatively deep down- I Wardly deflecting channels 3 and 4, which are of curved cross section.

The channels 3 and 4 terminate at their exterior sides in auxiliary planing surfaces 7 and 8, which begin as a narrow band near the bow and widen out to their maximum width just forward of the mid-section of the hull.

As the auxiliary planing surfaces are widened, they also gradually drop lower along the hull side from the point of beginning near the bow to amidships. Thereafter the planing surfaces continue in a constant horizontal level relative to the keel all the way to the stern of the boat. It will be noted that the dead rise or vertical angle of auxiliary planing surfaces 7 and 8 are greater than the dead rise angle of the inner planing surfaces 9 and ll) of the hull and are lessthan the dead rise angle of the sides of the hull thereabove.

The inner planing surfaces 9 and iii are the basic planing surfaces of the boat when running at high speed. i

The channels 3 and 4 are bounded on each side by inner chine lines 5 which also provide the inner edges of the auxiliary planing surfaces 7 and S. The auxiliary planing surfaces 7 and 8 are bounded on the outersides by outer chine lines 6.

It will be noted in FIGURE V that the inner chine lines 5 are lower, usually about 1 inch lower, than the adjoining surfaces of the high speed running bottoms 9 and Id.

Thus the inner chines 5, which are deeper as they progress toward the bow of the boat, form spray gathering Walls or strips from stem to stern of the boat. The heavy deep spray tunnel at the bow fades out ahead of midships into relatively narrow longitudinal spray chines.

When running forwardly through the water, the sharp bow 2 encounters waves and neatly splits them. The water runs up the sides of the bow into the channels 3 and 4 and is turned through to as it enters the bow channels 3 and 4. In so doing the deflected water is confined within the channels and gives up a large amount of its dynamic energy to the hull, which assists in lifting the bow over the waves smoothly and gently.

The transverse turning motion induced into the spray, together with the forward motion of the hull relative to the spray, results in a spiral action imparted to the spray,

such as indicated inlfhwhich is contained inside the inner chines 5 and'the. channels 3 and 4 as the spray progresses toward the stern of the boat.

When the; spray leaves at the transom, the.v resulting finelydividedgcloud of spr ay,'a'nd a small rooster, tail behind the hull. r r

Asithe boat reaches a speed of aboutZO miles per hour, the wetted surface is" substantially that shown in FIG- URE VI in'diagonal lines, as indicated by the numeral 12. It will be noted that the wetted surface extends above the inner chine line 5,, and include the auxiliary running surfaces 7 and 8.

As the speed increases to about 35 miles per hour, the

wettedsurface of the bottom of the hull is indicated by the numeral 13 inFlGURE VII. The outer chines 6 Q and'the auxiliary planing surfaces 7 and 8 runclear of the water, and substantially all water is passed backwardly along the channels 3 and/l to confine the dynamic force of the water Withinthe said channels to increase the lift of the boat and prevent side spray.

As'the speed of the boat increases to a higher speed,

the hull will be lifted .out' of the water more, but the mainplaning surfaces'l and ill will still contact the water and the force of the water will be confined between the inner chines 5. t Should the boat make a turn at high speed, the auxiliary planing surfaces 7 or 8 would contact the water in the directionof theturn as shown in FIG. VIII, wherein the wetted surface of the bottom of the hull is indicated in cross lines at 14. This stabilizesthe hull and minimizes. the lean into the turn to an acceptable angle and prevents increase in trim angle during such turn. 9 At the same time spray to the sides is virtuallyelirninated, V

At high speeds the auxiliary planing surfaces 7 and 8 are out of the water, and rise above the water leveL'and. the channels 3 and 4 contain all spray and convert the diverging masses of water split'by the bow and heel into 1 dynamic lift, .thus raising the hull in addition to the raising forces obtained from the planing action of the hull bottom. I I l V Thus this design substantially increases the speed of for stability. A

No poundingor slapping is experienced when the boat encounters waves running even as high as 12 .to 24inches;

A modification'is shown in FIGURES IX and X, wherein the design hereinbefore described is employed with the addition of one of more longitudinal sprayrails 15 pro- :the boat at given power and at the same time provides vided along the running surfaces 9 and 10 of the bottom of the hull. These auxiliary outwardly extending ribs appearance is one of no side spray along the hull, but 21 transverse sense.

the greater the 1iSt5-ti1 greater the lift, so thatwhenthe hull isrunning in a level condition, the spray rails on both 15. are provided to make the 'hull'less sensitive to offcenter loading conditions, such as is encountered when one person isdriving the boat or whenkthe load carried in the boat is placedofi-center, causing a list to theside on which the load is concentrated. L 1

When the hull lists toone side due to an imbalance in weight, an additional list is created by the. spray rails 15 on the side of the hull which is deeper in the water, causing thisrside of the bull to generate extra lift,-thus improving the balance and resulting in a more level'ride in a The spray rails 15 are so placed that sides createan equal amount of lift," thus causing no interference tolthe normal running of the hull.

. lt-will be understood that other and further'forms of the invention may be devised without departingfrom the spirit and scope of the appended claim.

Having described our invention, we claim:

In a boat having, a hull, a bow and'a sternya pair of parallel forward channels on "the bottom of the hull beginning at: a point near the bow, said channels being bordered on [the outer, edges by rel'ativelyhsteep Walls; a central longitudinal keel'disposed 'centrally of the hull separating the channels, the bottom of the hull onteach side of the keel within the channels being sloped upwardly from the keel to intersect the relatively steep walls; the said channels becoming progressively shallower and flatter from the-front to apoint nearthe center of the length of the hull at whichpoint they merge into substantially flanshaliow, inner planing surfaces which extend along'the bottom of the hull to a point near the stern,

References Cited in the filei'of' this patent UNITED STATES PATENTS 3,063,069 -Brurnmer Nov. 13, 1962 3,077,172 Dornak' Feb. 12,1963

3,077,851 Bamberger u Feb. 19,1963

McNeil Oct.

Hayman Mar. 21, 19 16 

